Genetics of Resistance to Soybean Cyst Nematode, Heterodera glycines Ichinohe (RACE 3), in a Brazilian Soybean Population
Antonio Orlando Mauro, Antonio Luiz de Oliveira and Sonia Marli Z. Mauro
Departamento de Fitotecnia, Faculdade de Ciências Agrárias e Veterinárias UNESP, Campus de Jaboticabal, 14870-000 Jaboticabal, SP, Brasil. Send correspondence to A.O.M. E-mail: [email protected]
Genet. Mol. Biol. vol.22 n.2 São Paulo June 1999. [Open Access]
A study was made of the genetics of resistance to the soybean cyst nematode, race 3, in a population derived from crosses between the Brazilian soybean genotypes BR 90-4722 and FT-Cristalina. Crosses between the two parents were made, the F1 and F2 generations were obtained and the population was analyzed for the number of cysts found in each plant of each generation as well as the type of reaction to the nematode. The results showed that resistance to the cyst nematode in this soybean population is of a qualitative nature and conditioned by three genes, one dominant and two recessives. The heritability of the character was very high (0.96), with minimum environmental effect, which means that this population is suitable for the development of soybean cultivars resistant to the cyst nematode.